Find an unknown coefficient

Steps

1. "f(x) is divisible by (x − a)" means f(a) = 0.
2. "Remainder r when divided by (x − a)" means f(a) = r.
3. Two conditions give two equations; solve them simultaneously.

For the whole topic, read More about polynomials: key points, common mistakes and how the DSE tests it.

Other methods in this topic